Fluoración enantioselectiva catalizada por iridio de los tricloroacetimidatos alilicos secundarios y racémicos
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Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
Published on: July 28, 2018
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Qi Zhang1, David P Stockdale1, Jason C Mixdorf1
1Department of Chemistry, University of Iowa , Iowa City, Iowa 52242, United States.
Journal of the American Chemical Society
|September 9, 2015
Resumen
Este estudio introduce un método eficiente catalizado por iridio para la fluoración asimétrica de compuestos alílicos. El nuevo enfoque proporciona acceso a valiosas moléculas que contienen flúor acíclico con alta estereoselectividad.
Área de la Ciencia:
- Química orgánica
- Química organometálica
- Química del fluor
Sus antecedentes:
- La fluoración enantioselectiva es crucial para sintetizar moléculas orgánicas quirales que contienen flúor.
- Los métodos anteriores para la fluoración enantioselectiva de sistemas alelicos tienen limitaciones, especialmente para los electrofilos alelicos secundarios con sustituyentes α-lineales.
Objetivo del estudio:
- Desarrollar un método suave y eficiente para la fluoración asimétrica de electrófilos racémios secundarios.
- Permitir la incorporación selectiva de fluoruro en sistemas alilicos acíclicos con una alta enantioselectividad.
Principales métodos:
- Se utilizó una reacción catalizada por iridio (Ir).
- Utilizó un complejo de Ir ligado a quiral-dieno como catalizador.
- Se utilizaron tricloroacetimidatos alilicos secundarios racémicos como sustratos y trifluoruro de trietilamina (Et3N·3HF) como fuente de fluoruro.
Principales resultados:
- Se ha logrado la fluoración enantioselectiva de los electrofilos racémicos secundarios.
- Se obtienen compuestos que contienen flúor acíclico en buenos rendimientos.
- Demostró excelentes niveles de inducción asimétrica, superando las limitaciones anteriores.
Conclusiones:
- La fluoración asimétrica catalizada por Ir desarrollada es una vía suave y eficiente para sintetizar valiosos compuestos fluorados acíclicos.
- Esta metodología amplía el alcance de la fluoración enantioselectiva, particularmente para desafiar sustratos alelicos secundarios.
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